精馏

The experiment gains reaction parameters of methylal from formaldehyde and methanol,it also found a mathematical model for continuous production process.

通过实验取得了甲醛和甲醇合成甲缩醛的反应参数；建立了其连续生产工艺的数学模型，利用ASPEN PLUS软件对甲醛和甲醇缩合生成甲缩醛进行了模拟，结果表明反应精馏连续生产甲缩醛的工艺是可行的，转化率高达99%，并得到含甲缩醛99%的产物，同时确定了进料板和反应区。

The possibility of preparation of methylal from methanol and formaldehyde through slurry catalytic distillation catalyzed by acidic cation exchange resin with large size pores is discussed.

研究了以甲醇和甲醛为原料，以大孔径强酸性阳离子交换树脂为催化剂，通过浆料催化精馏工艺制备甲缩醛的可行性。

Over a solid acid catalyst, the reaction in which methanol and formaldehyde are condensed into mathylal is reversible. This reaction tends to be completion by reactive distillation and the high-purity methylal product can be obtained.

在固体酸催化剂作用下，由甲醇、甲醛缩合生成甲缩醛，该反应为可逆反应，采用催化精馏技术可使反应趋于完全，并得到高纯度甲缩醛产品。

The experiment results indicate that: the increases of catalyst concentration, feed mole ratio of methanol to formaldehyde and the decrease of total feed flow can increase the yield of methylal; the concentration of methylal in distillate also increases with the increase of catalyst concentration; that the effects of reflux ratio on the yield and concentration of methylal in distillate are different from conventional distillation process, an optimal value of reflux ratio exists between 1 and 2 for this process.

实验结果表明：回流比对甲缩醛收率和塔顶甲缩醛纯度的影响不同于一般的精馏过程，存在一个最优回流比，本过程最佳回流比在1-2之间；提高催化剂浓度，甲缩醛收率和塔顶甲缩醛纯度均增加；提高进料醇醛摩尔比也会提高甲缩醛收率；进料总流量对甲缩醛的收率的影响十分明显，进料总流量减少可以使甲缩醛的收率得到明显提高。

The adoption of azeotropic rectification can produce the β-methylnaphthalene product with β-methylnaphthalene content over 95%, meanwhile α-methylnaphthalene product also can be produced.

摘 要：对β-甲基萘生产进行了研究和试验，采用共沸精馏可以生产出含量大于95%的β-甲基萘产品，同时还可以生产出α-甲基萘产品。

The distillation process is simulated by using Aspen Plus with the DSTWU fractionation module and the NRTL property method results showed that 99.9% methylnaphthalene and almost 100% tritoluene could be recovered.

利用Aspen Plus化工模拟软件的DSTWU精馏模块对产物进行模拟运算。结果表明：采用NRTL物性方法的模拟计算结果能够满足工艺要求，甲基萘回收率可达99.9%，溶剂回收率可达100%。

The following dehydration techniques of ethanol: distillation ,molecular sieve separation,membrane separation and corn adsorption are mainly concerned.

介绍了采用精馏法、分子筛分离法、膜分离法和作物吸附法制备无水乙醇的方法及其近年来无水乙醇制备的新进展。

High performance solvent N-formylmorpholinewas synthesized from morpholine and formic acid, dehydrated through the azeotrope rectifying method using water carrying agent A.

以吗啉和甲酸为原料，利用带水剂A通过共沸精馏的方法脱水，合成了高性能溶剂N-甲酰吗啉。

BED belongs to an unsteady state where the feed is strongly nonideal. A solution which is effective, quick and easy to run is hard to find out.

间歇萃取精馏属于非理想性极强的非稳态过程，很难找到一种快捷有效且易于执行的求解方法。

Secondary variables selecting method based on PCA is researched, and then secondary variables selecting method based on Partial Least-Squares Regression is proposed.

并且研究了基于主元分析的辅助变量选择方法，提出了基于偏最小二乘回归的辅助变量的选择方法，采用两种方法分别对常压精馏塔航空煤油干点的辅助变量进行了选择比较。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。